This module contains functions to launch LIO computations from
within the IO monad. These functions are not useful from within
LIO code (but not harmful either, since their types are in the
IO monad).

This module is intended to be imported into your Main module, for
use in invoking LIO code. The functions are also available via
LIO and LIO.Core, but those modules will clutter your namespace
with symbols you don't need in the IO monad.

Execute an LIO action, returning its result and the final label
state as a pair. Note that it returns a pair whether or not the
LIO action throws an exception. Forcing the result value will
re-throw the exception, but the label state will always be valid.

Given an LIO computation and some initial state, return an IO
action which, when executed, will perform the IFC-safe LIO
computation.

Because untrusted code cannot execute IO computations, this function
should only be useful within trusted code. No harm is done from
exposing the evalLIO symbol to untrusted code. (In general,
untrusted code is free to produce IO computations, but it cannot
execute them.)

Unlike runLIO, this function throws an exception if the
underlying LIO action terminates with an exception.

Initialize some privileges (within the IO monad) that can be
passed to LIO computations run with runLIO or evalLIO. This
is a pure function, but the result is encapsulated in IO to
make the return value inaccessible from LIO computations.

Note the same effect can be achieved using the PrivTCB
constructor, but PrivTCB is easier to misuse and is only available by
importing LIO.TCB.